Question

"a crane lifts a load upto a height of 8 m in half minute a second crane lifts the same load upto the same height in 15 seconds which supplies greater power and which consumes more fuel"

Answer 1

The first crane takes half minute ( 30 sec) and the second crane takes ( 15 sec) to do the same work. The second crane has more power as it lifts the same weight of load up to the same height in half the time as done by the first crane as power is given by P= $\frac{w}{t}$ and here w= mgh.
The second crane consumes more fuel than the first one.